Device for securing manway covers



July 12, 1949. I w ss 2,476,009

DEVICE FOR SECURING MANWAY COVERS Filed Aug. 12, 1946 ARA/0A0 14 555444 I N V EN TOR.

Patented July 12, 1949 DEVICE FOR SECURING MANWAY COVERS Arnold Wessman, Cedar Lake, Ind., assignor to C. F. Braun & C0,, Alhambra, Calif., a corporation of California Application August 12, 1946, Serial No. 689,967

6 Claims.

This invention relates to bubble columns of the type employed in oil refineries and oil cracking plants for fractionation, distillation, absorption and the like, and is particularly directed to improvements for securing manway covers in a position on the various trays within the bubble columns.

In conventional bubble column construction it has been customary to provide each of the trays in the bubble column with an opening or manway to enable a workman to travel from one end of the column to the other for cleaning, maintenance, inspection, etc. These manways are normally closed by, a cover plate which is secured in position on its respective tray by means of attachment fittings. It is desirable that the manway covers be releasable from either top or bottom so that a workman may move through the bubble column in either direction.

It is the principal object of this invention to provide a novel form of such an attachment device or fitting which may be releasable from either side of the bubble tray.

Another object is to provide securing means for a manway cover which is rugged in construction, inexpensive to manufacture, and easy to secure and release with ordinary tools.

A further object is to provide a releasable securing device of this type incorporating a wrench engageable lug adapted to contact a supporting ledge which is utilized for supporting the cover on the bubble tray.

Other objects and advantages will appear hereinafter.

In the drawings:

Figure 1 is a diagrammatic sectional elevation of a portion of a bubble column having manway covers secured to bubble trays by a preferred form of attachment device embodying my invention.

Figure 2 is a sectional plan view taken sub stantially on the line 22 as shown in Figure 1.

Figure 3 is a fragmental sectional elevation shown on an enlarged scale and demonstrating details of construction of the attachment device embodying my invention.

Figure 4 is a bottom view of the attachment fitting shown in Figure 3.

Figure 5 is an elevation view taken substantially on the line 55 as shown in Figure 3, the tray being omitted for clarity of illustration.

Referring to the drawings, bubble column generally designated is provided with a series of bubble trays, including trays ll, l2 and l3. Down-pipes l4, l5 and I6 are associated with each of the trays respectively to direct doWn- Wardly flowing fluid across each of the trays in turn. Each of the trays is provided with a plurality of bubble-caps I! and corresponding chimneys or vapor necks l8. Each bubble-cap l1 and its corresponding vapor neck l8 are maintained in proper relationship by means of a central bolt IS. The details of construction of the individual bubble-caps and vapor necks may be of any preferred form, the chief requirement being that an eflicient commingling be produced between gases rising through the vapor necks and the fluid flowing across the individual trays. The upper portion 20 of each down pipe serves as a weir to maintain proper depth of fiuid on the individual tray.

In order to provide access to the various trays of the column for purposes of maintenance and cleaning, openings or manways 2| are provided in each of the trays II, I 2 and [3. Cover plates 22, 23 and. 24 are provided in the trays ll, l2 and I3, respectively, for closing the manwa provided in each of the trays. A frame or ledge support 25 extending continuously around the opening 2| may be secured to the under side of the tray by means of welding 26. The details of construction of a preferred form of attachment device, as shown in Figure 3, will be described in connection with tray I2 and cover 23, although it will be understood that similar devices are employed for each of the other trays in the bubble column.

Suported on the ledge 25 is the manway 2-3 which has an exterior shape similar to the shape of the opening 2| within the tray I 2. A common method of forming the cover is to cut it from the material of the tray itself by a flame-cutting operation. When this method is employed, the shape of the cover and the shape of the corresponding opening are identical and the width of the flame-cut provides the necessary clearance for installation and removal of the cover. A threaded member 21, which may comprise a stud threaded end to end, extends through an aperture 28 provided in the cover plate 23. A square nut 29 may be threaded to a position intermediate the ends of member 21'and may be locked in place as by welding 30. A lug 3| is provided with the aperture 32 for reception of the threaded member 21 and is further provided with transversely spaced upwardl extended ears 33 and 34. The ears cooperate to define a recess 35 having substantially parallel sides and the square nut 29 is received within the recess 35 in non-rotatable relation. The ear 33 is shorter than the ear 34 in order that contact may be on the upper end of the member 21 and engages the upper surface of the cover plate 23-. TIT-he; cover plate 23 may be provided with vapor necks l8 and bubble-caps l1, if desired; as shown. in Figures 1 and 2.

Opposite sides 4! and 42 of the lug 3| are formed parallel to provide wrench engaging sur-- faces. Furthermore, the upper portion of the threaded member 21 is provided with wrench? flats 43. It will be understood from the construction= just described that the cover 23 may be secured to or released from the ledge 25, from either aboveor below the tray l2. Thus; a workman above the tray l2 first lowers the cover 2 3 intothe manway 2 l to permit. the cover 2-3- to rest on the flange or ledge 25;. Each of the threaded members 21 is then turned by means of applying a wrench to-the wrench flats-43. to rotate the ears 33 to a position directly under a portion of the ledge 25. The threaded member 21. is maintained in the selected angular position while'a second wrenchzis utilizedtoturn the nut 40. This-action brings the ears 33 and 34- into engagement with the ledge 25 and. cover 23. It will be apparent that the assembly may be removedv by workmen abovethe tray l2 by holding the wrench flats 43 againstrotation. while unthreading the nut 40;

The device may likewise be secured or removed .by a workman below the tray I2. Removalis effected by usingonewrenchon the surfaces M- and MY on the lug 3.! to prevent rotationof the lug. 3! and hence the member 21, while unthreadin the nut 38 with asecond wrench. The lug 34 may then be turned 90 so that theear 33'movesto. an

inoperative position. Likewise, the cover. may. be

securedinpositionon the ledge zfiby a workman below the tray I! by using one wrenchon the lug 31 and another onthe nut 38.

While the securing device has been shown. and

described as being mounted on the cover 23, it is recognized that it could be employed advantageously on thetray L2. This alternate construction will be readily understood by referring to Eigure-3 and considering thetray to-be thecover and: vice versa. In. such arrangementthe ledge 25 would. be secured to the cover,. while the threaded member 21 passedthrough. an aperture in the tray. Insuch. an inversionof. theparts, it mightalso bedesirable to place. the ledge. 25. on the top surface of thecover and, in such event, the lug 3lwould. likewise be located above. the tray.

These and. other variations and modifications may be employed. without departing from. the spiritof the invention and the device. described should. therefore be considered illustrative. onli, and. not as limiting. the scope of the claims.

Iclaim: 1

1; Ina device forsecuring amanway cover to a tray in a bubble column, the combination of. a,

threadedmember extending through anaperture irrthe'cover; alug encircling a portion of said threaded member and having a non-circular recess, the..lug having substantially parallel sidesto facilitate engagement by a wrench, a non-circular element fixed on said threaded member intermediate its ends and adapted to be non-rotatably received in said lug recess, a short ear on said lug at one side of said recess adapted to engage a ledge support for the cover, a long ear cn said lug at the other side of said recess adapted to engage the cover, a nut threaded on said memvber adapted to engage sa-idilugfia nut threaded on said member adapted toengage said cover, and wrench flats on the threaded member adjacent the last mentioned nut. V

2. In a device for. securing a manway cover to a tray in a bubble column, the combination of a threadedrmember; extending through an aperture in the cover, a lug encircling a portion of said threaded member and having a non-circular recess the lug having substantially parallel sides to facilitate engagement by a wrench, a non-circular element fixed on said threaded member intermediate its ends and: adapted to be non-rotatably received in saidlug recess,. a short ear, on said lug at one side of. said recess adapted to ens age a ledge support for the covery a: long. ear on said lug at the. other side ofi said; recess adapted: to engage the cover, the engaging: portions of said lug ears being curved. to avoidsurface.contact,.a nut threaded on said member adapted toengagesaid lug, a. nut threaded. on; saidmemberl adapted to engage saidcover,. anduwrench flats. on the threaded member adjacent. the. last mentioned nut.

3. In a. device for. securinga cover. plate within an. opening in a. bubble column tray platathe combination. of aledgeelement secured to oneoi the plates and. adapted.- toextend. continuously; aboutsaid opening, a threaded member. extending through an apertureintheother plate,.,means on the threadedmember releasable from either side of the tray plate adapted to-maintaintheledge element and apertured.platerinqengagement, said means including. a. wrench. engageablefllug, encir cling. a. portion oisaid threadedlmember: and hav ing a non-circular recess, amen-circular element. fixed on, said. thread-ed member...intermediatev its ends and adapted. to .be non-rotatabl-y receivedin adapted to engage the apertured platesandimeans onthe member adjacent. the last -mentioned-. nu for preventing rotation of said member.

4. In a device for securing a cover plate within an opening in a bubble column tray plate,,. the combination ofaledge element secured te-one, of the plates and adapted to '-ertend continuously about said opening, a I threaded. member extend ing through an apertureinthe-othenplate, .means on. the threadedmember releasable fromeither side of the tray plate:- adapted to maintain the ledge element-and apertured'plate inengagemente saidmeans including a. wrenchengageable lug. encircling a portion of said. threaded member" and having anon-circular. recessnalncmcircular element fixed on said threaded membeninterme diate its. ends and. adapted: to be. non-rotatably received'in saidalug recess, said-lug having-a short ear at one side of said ,recessadapted to engagei plate, the engaging' portions otsaid lug-earsbeihgf curved-to avoid surface contact, a -nut threaded on nd membertad p ed to engace itheelug;.a'nuh threaded on said member and adapted to engage the apertured plate, and means on the member adjacent the last mentioned nut for preventing rotation of said member.

5. In a device for securing a cover plate within an opening in a bubble column tray plate, the combination of a ledge element secured to one of the plates and adapted to extend continuously about said opening, a lug having a short rounded ear adapted to engage the ledge element and a long rounded ear adapted to engage the other plate, and means releasable from either side of the tray plate for maintaining the lug ears in engagement, said means including a threaded member extending through the lug and through one of said plates, said member being non-rotatably secured relative to said lug.

6. In a device for securing a cover plate within an opening in a bubble column tray plate, the

cover plate having a ledge element secured there- REFERENCES CITED The following references are of record in the file of this patent:

UNITED v STATES PATENTS Name Date Harrington Nov. 2, 1920 Number 

